Even though LinkedIn's growth was incredible between March 2011 and September 2012, with its sales growing across all of its revenue streams (premium subscriptions, recruitment, and advertising), it needs to look for external growth opportunities in order to maintain that pace.

But analysts have mixed opinions for what LinkedIn should do next.

Rick Summer, a senior equity analyst at Morningstar, told Loizos that he sees a day where LinkedIn looks "more like a software company, managing job candidates from their sourcing to managing the candidate inside the walls of a company."

With that in mind, Summer says that SilkRoad, a 10-year-old employee management software company, could be a good acquisition target.

Other analysts say LinkedIn should also consider acquiring these companies: